There are two bases for filing a trademark application in the United States: current use and intent to use.
In use: If you are basing your trademark application on “current use,” you must include a sworn statement (usually in the form of a declaration) that the mark is in use in commerce, listing the date of first use of the mark anywhere and the date of first use of the mark in commerce. You must also include a specimen showing the use of the mark in commerce. For specimen of goods, the mark must appear on the goods, the container for the goods, or displays associated with the goods, and the goods must be sold or transported in commerce. For specimen of services, the mark must be used or displayed in the sale or advertising of the services and the services must be rendered in commerce.

Intent to use: If you have not yet used the mark, but plan to do so in the future, you may file an application based on a good faith intention to use the mark in commerce. You do not have to use the mark before you file your application. An "intent to use" application must include a sworn statement (usually in the form of a declaration) that you have a bona fide intention to use the mark in commerce.